The present invention relates to a fabric guide device for a sewing machine, and more particularly to a fabric guide device for a sewing machine used at overlaying over-edge chain stitching portions individually formed in upper and lower bodies face to face, and sewing together the overlapped portions.
A sewing process includes a specification of opening a body obtained by executing over-edge chain stitching to two fabrics, folding its over-edge chain stitching portion face to face, and sewing together the folded portion. In such specification, as shown in FIG. 4, when the over-edge chain stitching portions (Wc, Wc) in raised state come beneath the presser foot, the over-edge chain stitching portions (Wc, Wc) are usually tilted backward. At this time, these portions are overlapped or squeezed, and a large step is formed to lower the product quality.
Japanese Laid-open Patent No. H05-76678 discloses a fabric guide device designed to prevent from forming bulkiness in the over-edge chain stitching portions in upper and lower bodies by using a pair of tilting pawls. This device is disposed on a sewing machine table before the sewing machine bed, and the pair of tilting pawls are designed to guide to tilt down the over-edge chain stitching portions in the upper and lower bodies. This device can be applied to the bodies in which the over-edge chain stitching portions project outward, but cannot be applied to the bodies in which the over-edge chain stitching portions face each other between the bodies, and moreover since the fabric guide device is disposed on the sewing machine table before the sewing machine bed, a space for the sewing machine table is needed before the sewing machine bed.
It is hence an object of the invention to present a fabric guide device for a sewing machine capable of operating to tilt in one direction prior to sewing operation of over-edge chain stitching portions mutually projecting between bodies, and downsizing or omitting the sewing machine table before the sewing machine bed.
The fabric guide device for a sewing machine according to the present invention is used at sewing overlaid portion together by overlaying over-edge chain stitching portion face to face after opening a body obtained by executing over-edge chain stitching to two fabrics, and it is disposed at the fabric feed side from the presser foot of the sewing machine. This fabric guide device is composed of upper plate and middle plate. The upper plate is disposed on the sewing machine bed in a state of keeping a certain clearance from the sewing machine bed, and its fabric feed side portion is warped upward. The middle plate is disposed beneath the warped portion of the upward warp of the upper plate, and is free to project and retreat from and into the sewing machine bed. The middle plate has upper and lower surfaces for guiding the fabrics.
At the time of sewing, the body is overlaid so that its over-edge chain stitching portion may face each other prior to sewing, and is fed into the fabric guide device while handling under the presser foot. Consequently, the middle plate projects from the sewing machine bed to interpose between upper and lower bodies before the over-edge chain stitching portions, and when said bodies are pulled out to the front side in this state, the over-edge chain stitching portions abut against the middle plate and tilt in the fabric feed direction. In this state, the fabrics are further pulled out, and the tilted over-edge chain stitching portions are positioned beneath the presser foot. At this time, since the bodies pulling direction is opposite to the tilting direction of the over-edge chain stitching portions, and the tilted over-edge chain stitching portions are not raised when the bodies are pulled, and remain in tilted state at the time of pulling. The presser foot is lowered while the over-edge chain stitching portions are positioned beneath the presser foot, and the fabrics are seamed.
According to the present invention, the over-edge chain stitching portions projecting face to face between upper and lower bodies can be tilted in the fabric feed direction by simple operation of fabric manipulation and middle plate manipulation, and the job burden of the operator is less and the productivity is enhanced.
Besides, since the fabric guide device of the present invention is disposed in the sewing machine bed, sewing machine table for disposing the fabric guide device is not needed before the sewing machine bed, and if a sewing machine table is provided, since the fabric guide device is not mounted on it, the size of the sewing machine table can be reduced.
The middle plate of the present invention is preferred to have a perpendicular surface at the fabric feed side. By pulling the fabrics to the front side while the over-edge chain stitching portions are in contact with the perpendicular surface of the middle plate, the over-edge chain stitching portions are tilted more securely.
Other features and effects of the present invention will be more clearly understood in the following detailed description of the embodiments by those skilled in the art. It must be, however, noted that the technical scope of the present invention is not limited to the embodiments and the accompanying drawings alone.